A method including determining whether an apparatus is to operate in a first, second or third mode of operation; wherein said first mode of operation includes a first level of activity, said second mode of operation includes a second level of activity that is lower than said first level of activity, and said third mode of operation includes a third level of activity that is lower than said second level of activity; applying a first reference signal transmission regime when in said second mode of operation; and applying a second reference signal transmission regime when in said third mode of operation.
|
1. A method comprising:
determining whether a base station is to operate in a first, second or third mode of operation, wherein said first mode of operation is associated with a long active state of the base station, said second mode of operation is associated with a short active state and a short dormancy state of the base station and said third mode of operation is associated with a long dormancy state of the base station;
wherein said first mode of operation comprises a first level of activity in which data and at least one type of reference signal are sent, said second mode of operation comprises a second level of activity that is lower than said first level of activity in which at least one type of the reference signal is sent, and said third mode of operation comprises a third level of activity that is lower than said second level of activity, wherein said data is included in communication of traffic with a user equipment when in said first mode of operation, the user equipment performs data transmission only when the base station is in the long active state, and said at least one type of reference signal comprises a synchronization signal for the user equipment when in said first mode of operation, including one or more of a primary synchronization signal (PSS) used for synchronization with a primary cell (P-cell) or a secondary synchronization signal (SSS) used for synchronization with a secondary cell (S-cell);
applying a first reference signal transmission regime from the base station to the user equipment during the short dormancy state in which a plurality of said at least one type of reference signal are sent less often than when operating at the first level of activity, with no further data transmission being made, when in said second mode of operation, wherein when the user equipment has synchronized with the P-cell or S-cell that includes the base station and the base station is in the short dormancy state, to maintain a connection of the user equipment with the base station within the P-cell or S-cell, there is no data transmission by the user equipment with the base station, but the user equipment performs one or more measurements of the at least one type of reference signal and reports the one or more measurements; and
applying a second reference signal transmission regime in which no data nor reference signals are sent from the base station, when in said third mode of operation.
13. A method comprising:
receiving, at a user equipment, information regarding a level of activity of a base station, wherein said information comprises information regarding one of: a long dormancy state; a short dormancy state; and a long active state of said base station in which data and at least one type of reference signal are sent; and
configuring a radio resource control, rrc mode of said user equipment with said base station in dependence on said information, wherein said rrc mode comprises a first rrc mode being a rrc connected mode or a second rrc mode being a rrc idle mode, wherein said first rrc mode is associated with the long active state of the base station and the short dormancy state of the base station, said second rrc mode is associated with the long dormancy state of the base station, and wherein said data is included in communication of traffic with the user equipment such that the user equipment performs data transmission only when the base station is in the long active state, and said at least one type of reference signal comprises a synchronization signal for the user equipment when the base station is in the long active state, including one or more of a primary synchronization signal (PSS) used for synchronization with a primary cell (P-cell) or a secondary synchronization signal (SSS) used for synchronization with a secondary cell (S-cell);
wherein said first rrc mode comprises a first level of activity and said first rrc mode is configured when said state of said base station is either of said short dormancy state or said long active state, and said second rrc mode comprises a second level of activity that is lower than said first level of activity and said second rrc mode is configured when said state of said base station is said long dormancy state, wherein in said first rrc mode when said state of said base station is said short dormancy state, no further data transmission is received from said base station, wherein in said second rrc mode, no data transmission nor reference signal transmission is received from said base station, and wherein when the user equipment has synchronized with the P-cell or S-cell that includes the base station, and the base station is in the short dormancy state, to maintain a connection of the user equipment with the base station within the P-cell or S-cell, there is no data transmission by the user equipment with the base station, but the user equipment performs one or more measurements of the at least one type of reference signals and reports the one or more measurements.
7. A base station comprising
at least one processor;
and at least one memory including computer program code;
the at least one memory and the computer program code configured to, with the at least one processor, cause the base station at least to:
determine whether to operate the base station in a first, second or third mode of operation, wherein said first mode of operation is associated with a long active state of the base station, said second mode of operation is associated with a short active state and a short dormancy state of the base station, and said third mode of operation is associated with a long dormancy state of the base station, wherein said first mode of operation comprises a first level of activity in which data and at least one type of reference signal are sent, said second mode of operation comprises a second level of activity that is lower than said first level of activity in which at least one type of the reference signal is sent, and said third mode of operation comprises a third level of activity that is lower than said second level of activity, and wherein said data is included in communication of traffic with a user equipment when in said first mode of operation, the user equipment performs data transmission only when the base station is in the long active state, and said at least one type of reference signal comprises a synchronization signal for the user equipment when in said first mode of operation, including one or more of a primary synchronization signal (PSS) used for synchronization with a primary cell (P-cell) or a secondary synchronization signal (SSS) used for synchronization with a secondary cell (S-cell);
apply a first reference signal transmission regime from the base station to the user equipment during the short dormancy state in which a plurality of said at least one type of reference signal are sent less often than when operating at the first level of activity, with no further data transmission being made, when in said second mode of operation, wherein when the user equipment has synchronized with the P-cell or S-cell that includes the base station, and the base station is in the short dormancy state, to maintain a connection of the user equipment with the base station within the P-cell or S-cell, there is no data transmission by the user equipment with the base station, but the user equipment performs one or more measurements of the at least one type of reference signal and reports the one or more measurements;
and apply a second reference signal transmission regime in which no data nor reference signals are sent from the base station, when in said third mode of operation.
17. A computer program embodied in a non-transitory computer-readable medium comprising computer executable instructions which, when run on one or more processors, perform the method comprising:
receiving, at a user equipment, information regarding a level of activity of a base station, wherein said information comprises information regarding one of: a long dormancy state; a short dormancy state; and a long active state of said base station in which data and at least one type of reference signal are sent; and
configuring a radio resource control, rrc mode of said user equipment with said base station in dependence on said information, wherein said rrc mode comprises a first rrc mode being a rrc connected mode or a second rrc mode being a rrc idle mode, wherein said first rrc mode is associated with the long active state of the base station and the short dormancy state of the base station, said second rrc mode is associated with the long dormancy state of the base station, and wherein said data is included in communication of traffic with the user equipment such that the user equipment performs data transmission only when the base station is in the long active state, and said at least one type of reference signal comprises a synchronization signal for the user equipment when the base station is in the long active state, including one or more of a primary synchronization signal (PSS) used for synchronization with a primary cell (P-cell) or a secondary synchronization signal (SSS) used for synchronization with a secondary cell (S-cell);
wherein said first rrc comprises mode a first level of activity and said first rrc mode is configured when said state of said base station is either of said short dormancy state or said long active state, and said second rrc mode comprises a second level of activity that is lower than said first level of activity and said second rrc mode is configured by said user equipment when said state of said base station is said long dormancy state, wherein in said first rrc mode when said state of said base station is said short dormancy state, no further data transmission is received from said base station, wherein in said second rrc mode, no data transmission nor reference signal transmission is received from said base station, and wherein when the user equipment has synchronized with the P-cell or S-cell that includes the base station, and the base station is in the short dormancy state, to maintain a connection of the user equipment with the base station within the P-cell or S-cell, there is no data transmission by the user equipment with the base station, but the user equipment performs one or more measurements of the at least one type of reference signals and reports the one or more measurements.
15. A user equipment comprising
at least one processor;
and at least one memory including computer program code;
the at least one memory and the computer program code configured to, with the at least one processor, cause the user equipment at least to:
receive information regarding a level of activity of a base station, wherein said information comprises information regarding one of: a long dormancy state; a short dormancy state; and n long active state of said base station in which data and at least one type of reference signal are sent; and
configure a radio resource control, rrc mode of said user equipment with said base station in dependence on said information, wherein said rrc mode comprises a first rrc mode being a rrc connected mode or a second rrc mode being a rrc idle mode, wherein said first rrc mode is associated with the long active state of the base station and the short dormancy state of the base station, said second rrc mode is associated with the long dormancy state of the base station, and wherein said data is included in communication of traffic with the user equipment such that the user equipment performs data transmission only when the base station is in the long active state, and said at least one type of reference signal comprises a synchronization signal for the user equipment when the base station is in the long active state, including one or more of a primary synchronization signal (PSS) used for synchronization with a primary cell (P-cell) or a secondary synchronization signal (SSS) used for synchronization with a secondary cell (S-cell);
wherein said first rrc mode comprises a first level of activity and said first rrc mode is configured by said user equipment when said state of said base station is either of said short dormancy state or said long active state, and said second rrc mode comprises a second level of activity that is lower than said first level of activity and said second rrc mode is configured by said user equipment when said state of said base station is said long dormancy state, wherein in said first rrc mode when said state of said base station is said short dormancy state, no further data transmission is received from said base station, wherein in said second rrc mode, no data transmission nor reference signal transmission is received from said base station, and wherein when the user equipment has synchronized with the P-cell or S-cell that includes the base station, and the base station is in the short dormancy state, to maintain a connection of the user equipment with the base station within the P-cell or S-cell, there is no data transmission by the user equipment with the base station, but the user equipment performs one or more measurements of the at least one type of reference signals and reports the one or more measurements.
2. A method as set forth in
3. A method as set forth in
4. A method as set forth in
5. A method as set forth in
6. A method as set forth in
8. A base station as set forth in
9. A base station as set forth in
10. A base station as set forth in
11. A base station as set forth in
12. A base station as set forth in
14. A method as set forth in
16. A user equipment as set forth in
18. The method of
|
This disclosure relates to methods and apparatus and in particular but not exclusively to methods and apparatus for use where a cell or node has multiple activity levels.
A communication system can be seen as a facility that enables communication sessions between two or more nodes such as fixed or mobile devices, machine-type terminals, access nodes such as base stations, servers and so on. A communication system and compatible communicating entities typically operate in accordance with a given standard or specification which sets out what the various entities associated with the system are permitted to do and how that should be achieved. For example, the standards, specifications and related protocols can define the manner how devices shall communicate, how various aspects of communications shall be implemented and how devices for use in the system shall be configured.
A user can access the communication system by means of an appropriate communication device. A communication device of a user is often referred to as user equipment (UE) or terminal. A communication device is provided with an appropriate signal receiving and transmitting arrangement for enabling communications with other parties. Typically a device such as a user equipment is used for enabling receiving and transmission of communications such as speech and content data.
Communications can be carried on wireless carriers. Examples of wireless systems include public land mobile networks (PLMN) such as cellular networks, satellite based communication systems and different wireless local networks, for example wireless local area networks (WLAN). In wireless systems a communication device provides a transceiver station that can communicate with another communication device such as e.g. a base station of an access network and/or another user equipment. The two directions of communications between a base station and communication devices of users have been conventionally referred to as downlink and uplink. Downlink (DL) can be understood as the direction from the base station to the communication device and uplink (UL) the direction from the communication device to the base station.
In a first aspect there is provided a method comprising: determining whether an apparatus is to operate in a first, second or third mode of operation; wherein said first mode of operation comprises a first level of activity, said second mode of operation comprises a second level of activity that is lower than said first level of activity, and said third mode of operation comprises a third level of activity that is lower than said second level of activity; applying a first reference signal transmission regime when in said second mode of operation; and applying a second reference signal transmission regime when in said third mode of operation.
Preferably the method comprises moving from any one of said first, second and third modes of operation to any other of said first, second and third modes of operation.
Preferably the method comprises operating in said first mode of operation when a parameter satisfies a first threshold level, operating in said second mode of operation when said parameter satisfies a second threshold level that is lower than said first threshold level, and operating in said third mode of operation when said parameter satisfies a third threshold level that is lower than said second threshold level.
Preferably said parameter comprises at least one of: a cell-load, a neighbouring eNB requirement; paging information; user equipment triggering information.
Preferably said first reference signal transmission regime comprises transmitting at least one reference signal with a first time interval.
Preferably said second reference signal transmission regime comprises transmitting at least one reference signal with a second time interval that is longer than said first time interval.
Preferably said first mode of operation is associated with an active state of a base station, said second mode of operation is associated with a short dormancy state of a base station; and said third mode of operation is associated with a long dormancy state of a base station.
Alternatively said second reference signal transmission regime comprises not transmitting any reference signals.
Preferably said at least one reference signal comprises one of: a synchronization signal for a user equipment; a common reference signal; a discovery signal.
Preferably said determining whether an apparatus is to operate in said first, second or third mode of operation is dependent upon a network determination.
Alternatively said determining whether an apparatus is to operate in said first, second or third mode of operation is dependent upon user equipment triggering.
Preferably said method comprises one or both of transmitting and receiving data when in said first mode of operation only.
Preferably said method comprises de-activating a transmitter and/or receiver of said apparatus when operating in said second mode of operation or said third mode of operation.
Preferably said first mode of operation comprises applying a reference signal transmission regime in which a common reference signal is transmitted in every subframe.
Preferably said apparatus comprises a base station.
In another aspect there is provided a computer program comprising computer executable instructions which when run on one or more processors performs the method set out above.
In another aspect there is provided an apparatus comprising at least one processor;
and at least one memory including computer program code; the at least one memory and the computer program code configured to, with the at least one processor, cause the apparatus at least to: determine whether to operate in a first, second or third mode of operation; wherein said first mode of operation comprises a first level of activity, said second mode of operation comprises a second level of activity that is lower than said first level of activity, and said third mode of operation comprises a third level of activity that is lower than said second level of activity; apply a first reference signal transmission regime when in said second mode of operation; and apply a second reference signal transmission regime when in said third mode of operation.
Preferably the apparatus is configured to move from any one of said first, second and third modes of operation to any other of said first, second and third modes of operation.
Preferably said apparatus is configured to operate in said first mode of operation when a parameter satisfies a first threshold level, operate in said second mode of operation when said parameter satisfies a second threshold level that is lower than said first threshold level, and operate in said third mode of operation when said parameter satisfies a third threshold level that is lower than said second threshold level.
Preferably said parameter comprises at least one of: a cell-load, a neighbouring eNB requirement; paging information; user equipment triggering information.
Preferably said first reference signal transmission regime comprises transmitting at least one reference signal with a first time interval.
Preferably said second reference signal transmission regime comprises transmitting at least one reference signal with a second time interval that is longer than said first time interval.
Preferably said first mode of operation is associated with an active state of a base station, said second mode of operation is associated with a short dormancy state of a base station; and said third mode of operation is associated with a long dormancy state of a base station.
Alternatively said second reference signal transmission regime comprises not transmitting any reference signals.
Preferably said at least one reference signal comprises one of: a synchronization signal for a user equipment; a common reference signal; a discovery signal.
Preferably said determining whether to operate in said first, second or third mode of operation is dependent upon a network determination.
Alternatively said determining whether to operate in said first, second or third mode of operation is dependent upon user equipment triggering.
Preferably said apparatus is configured to one or both of: transmit and receive data when in said first mode of operation only.
Preferably said apparatus is configured to de-activate a transmitter and/or receiver of said apparatus when operating in said second mode of operation or said third mode of operation.
Preferably when in said first mode of operation said apparatus is configured to apply a reference signal transmission regime in which a common reference signal is transmitted in every subframe.
Preferably said apparatus comprises a base station.
According to another aspect there is provided an apparatus comprising: means for determining whether to operate in a first, second or third mode of operation;
wherein said first mode of operation comprises a first level of activity, said second mode of operation comprises a second level of activity that is lower than said first level of activity, and said third mode of operation comprises a third level of activity that is lower than said second level of activity; and means for applying a first reference signal transmission regime when in said second mode of operation; and applying a second reference signal transmission regime when in said third mode of operation.
Preferably the apparatus comprises means for moving from any one of said first, second and third modes of operation to any other of said first, second and third modes of operation.
Preferably said apparatus is configured to operate in said first mode of operation when a parameter satisfies a first threshold level, operate in said second mode of operation when said parameter satisfies a second threshold level that is lower than said first threshold level, and operate in said third mode of operation when said parameter satisfies a third threshold level that is lower than said second threshold level.
Preferably said parameter comprises at least one of: a cell-load, a neighbouring eNB requirement; paging information; user equipment triggering information.
Preferably said first reference signal transmission regime comprises transmitting at least one reference signal with a first time interval.
Preferably said second reference signal transmission regime comprises transmitting at least one reference signal with a second time interval that is longer than said first time interval.
Preferably said first mode of operation is associated with an active state of a base station, said second mode of operation is associated with a short dormancy state of a base station; and said third mode of operation is associated with a long dormancy state of a base station.
Alternatively said second reference signal transmission regime comprises not transmitting any reference signals.
Preferably said at least one reference signal comprises one of: a synchronization signal for a user equipment; a common reference signal; a discovery signal.
Preferably said determining whether to operate in said first, second or third mode of operation is dependent upon a network determination.
Alternatively said determining whether to operate in said first, second or third mode of operation is dependent upon user equipment triggering.
Preferably said apparatus is configured to one or both of: transmit and receive data when in said first mode of operation only.
Preferably said apparatus comprises means for de-activating a transmitter and/or receiver of said apparatus when operating in said second mode of operation or said third mode of operation.
Preferably when in said first mode of operation said apparatus is configured to apply a reference signal transmission regime in which a common reference signal is transmitted in every subframe.
Preferably said apparatus comprises a base station.
In another aspect there is provided a method comprising: receiving, at a first apparatus, information regarding a level of activity of a second apparatus; configuring a connection mode of said first apparatus with said second apparatus in dependence on said information, wherein said connection mode comprises a first connection mode or a second connection mode; and said first connection mode comprises a first level of activity, and said second connection mode comprises a second level of activity that is lower than said first level of activity.
Preferably said information comprises information regarding one of: a long dormancy state; a short dormancy state; and an active state of said second apparatus.
Preferably said method comprises configuring said second connection mode when said state of said second apparatus is said long dormancy state, and configuring said first connection mode when said state of said second apparatus is either of said short dormancy state or said active state.
Preferably said first connection mode is a radio resource connection mode and said second connection mode is a radio resource connection idle mode.
Preferably data transmission is prohibited from said first apparatus to said second apparatus when said first apparatus is in said radio resource connection mode and said second apparatus is in said short dormancy state.
Preferably said method comprises moving from any of said first and second connection mode to the other of said first and second connection mode.
Preferably wherein when in said first connection mode said method comprises at least one of transmitting data to and receiving data from said second apparatus.
Preferably said method comprises using said information for synchronization between said first apparatus and said second apparatus.
Preferably said first apparatus comprises a user equipment.
In another aspect there is provided a computer program comprising computer executable instructions which when run on one or more processors perform the method as set out above.
In another aspect there is provided an apparatus comprising at least one processor;
and at least one memory including computer program code; the at least one memory and the computer program code configured to, with the at least one processor, cause the apparatus at least to: receive information regarding a level of activity of a second apparatus; configure a connection mode of said apparatus with said second apparatus in dependence on said information, wherein said connection mode comprises a first connection mode or a second connection mode; and said first connection mode comprises a first level of activity, and said second connection mode comprises a second level of activity that is lower than said first level of activity.
Preferably said information comprises information regarding one of: a long dormancy state; a short dormancy state; and an active state of said second apparatus.
Preferably said apparatus is configured to configure said second connection mode when said state of said second apparatus is said long dormancy state, and configure said first connection mode when said state of said second apparatus is either of said short dormancy state or said active state.
Preferably said first connection mode is a radio resource connection mode and said second connection mode is a radio resource connection idle mode.
Preferably said apparatus is configured to prohibit data transmission to said second apparatus when said apparatus is in said radio resource connection mode and said second apparatus is in said short dormancy state.
Preferably said apparatus is configured to move from any of said first and second connection mode to the other of said first and second connection mode.
Preferably when in said first connection mode said apparatus is configured to at least one of transmit data to and receive data from said second apparatus.
Preferably said apparatus is configured to use said information for synchronization between said apparatus and said second apparatus.
Preferably said apparatus comprises a user equipment.
An apparatus comprising: means for receiving information regarding a level of activity of a second apparatus; means for configuring a connection mode of said apparatus with said second apparatus in dependence on said information, wherein said connection mode comprises a first connection mode or a second connection mode; and said first connection mode comprises a first level of activity, and said second connection mode comprises a second level of activity that is lower than said first level of activity.
Preferably said information comprises information regarding one of: a long dormancy state; a short dormancy state; and an active state of said second apparatus.
Preferably said apparatus comprises means for configuring said second connection mode when said state of said second apparatus is said long dormancy state, and for configuring said first connection mode when said state of said second apparatus is either of said short dormancy state or said active state.
Preferably said first connection mode is a radio resource connection mode and said second connection mode is a radio resource connection idle mode.
Preferably said apparatus comprises means for prohibiting data transmission to said second apparatus when said apparatus is in said radio resource connection mode and said second apparatus is in said short dormancy state.
Preferably said apparatus comprises means for moving from any of said first and second connection mode to the other of said first and second connection mode.
Preferably wherein when in said first connection mode said apparatus comprises means for at least one of transmitting data to and receiving data from said second apparatus.
Preferably said apparatus comprises means for using said information for synchronization between said apparatus and said second apparatus.
Preferably said apparatus comprises a user equipment.
Embodiments will now be described in further detail, by way of example only, with reference to the following examples and accompanying drawings, in which:
In the following certain exemplifying embodiments are explained with reference to a wireless or mobile communication system serving mobile communication devices. Before explaining in detail the exemplifying embodiments, certain general principles of a wireless communication system and mobile communication devices are briefly explained with reference to
In a wireless communication system mobile communication devices or user equipment (UE) 102, 103, 105 are provided wireless access via at least one base station or similar wireless transmitting and/or receiving node or point. In the
Base stations are typically controlled by at least one appropriate controller apparatus so as to enable operation thereof and management of mobile communication devices in communication with the base stations. In
LTE systems may be considered to have a so-called “flat” architecture, without the provision of RNCs; rather the (e)NB is coupled to a serving gateway (S-GW) and/or mobility management entity (MME), which entities may also be pooled meaning that a plurality of these nodes may serve a plurality (set) of (e)NBs. Each UE is served by only one MME and/or S-GW at a time and the (e)NB keeps track of current association.
In the future some operations or functionalities of an (e)NB may be carried out by cloud services in which case the “base station” may comprise a combination of a remote radio head (RRH) and server or host. Furthermore, according to the “liquid” or flexible radio concept, the operations and functionalities may be performed in different entities, such as a node, host or server, in a flexible manner. In other words, “division of labour” may vary case by case. One possible use is to make a base station deliver local content.
In
The smaller stations 116, 118 and 120 can also be connected to the network 113, for example by a separate gateway function and/or via the controllers of the macro level stations. In the example, stations 116 and 118 are connected via a gateway 111 whilst station 120 connects via the controller apparatus 108. In some embodiments, the smaller stations may not be provided. It should be appreciated that the system may also comprise other kind of nodes such as relay nodes or so-called plug-in nodes or home nodes.
A possible mobile communication device will now be described in more detail with reference to
The mobile device 102 may receive signals over an air interface 207 via appropriate apparatus for receiving and may transmit signals via appropriate apparatus for transmitting radio signals. In
A wireless communication device can be provided with a Multiple Input/Multiple Output (MIMO) antenna system. MIMO arrangements as such are known. MIMO systems use multiple antennas at the transmitter and receiver along with advanced digital signal processing to improve link quality and capacity. Although not shown in
A mobile device is typically provided with at least one data processing entity 201, at least one memory 202 and other possible components 203 for use in software and hardware aided execution of tasks it is designed to perform, including control of access to and communications with access systems and other communication devices. The data processing, storage and other relevant control apparatus can be provided on an appropriate circuit board and/or in chipsets. This feature is denoted by reference 204. The user may control the operation of the mobile device by means of a suitable user interface such as key pad 205, voice commands, touch sensitive screen or pad, combinations thereof or the like. A display 208, a speaker and a microphone can be also provided. Furthermore, a mobile communication device may comprise appropriate connectors (either wired or wireless) to other devices and/or for connecting external accessories, for example hands-free equipment, thereto.
The communication devices 102, 103, 105 can access the communication system based on various access techniques, such as code division multiple access (CDMA), or wideband CDMA (WCDMA). Other examples include time division multiple access (TDMA), frequency division multiple access (FDMA) and various schemes thereof such as the interleaved frequency division multiple access (IFDMA), single carrier frequency division multiple access (SC-FDMA) and orthogonal frequency division multiple access (OFDMA), space division multiple access (SDMA) and so on.
An example of wireless communication systems are architectures standardized by the 3rd Generation Partnership Project (3GPP). A latest 3GPP based development is often referred to as the long-term evolution (LTE) of the Universal Mobile Telecommunications System (UMTS) radio-access technology. The various development stages of the 3GPP LTE specifications are referred to as releases.
More recent developments of the LTE are often referred to as LTE Advanced (LTE-A or LTE-Advanced). The LTE employs a mobile architecture known as the Evolved Universal Terrestrial Radio Access Network (E-UTRAN). Base stations of such systems are known as evolved or enhanced Node Bs (eNBs) and may provide E-UTRAN features such as user plane Radio Link Control/Medium Access Control/Physical layer protocol (RLC/MAC/PHY) and control plane Radio Resource Control (RRC) protocol terminations towards the communication devices. Other examples of radio access system include those provided by base stations of systems that are based on technologies such as wireless local area network (WLAN) and/or WiMax (Worldwide Interoperability for Microwave Access). In the future, the radio access system may be beyond 4th generation (B4G) system, which is designed to be based on a similar kind of architecture as the LTE-Advanced.
As part of 3GPP Release 12 a work item on NCT (new carrier type) has been proposed and agreed. The carrier may be used in such a way in order to achieve one or more of the following aims: network energy-saving; overhead reduction; and enhanced support for arrangements which include one or more smaller cell(s) at least partially overlying a larger cell. Some arrangements where one or more smaller cells overlie a larger cell (for example a macro cell) are sometimes referred to as HetNet arrangements.
To allow for network energy savings, a base station may be controlled to allow for completely blank subframes when there is no data to transmit. This means that the transmitter can be at least partially shut down.
An overhead reduction may be achieved by reducing the CRS (common reference signal) overhead in situations where the DM RS (demodulation reference signal) may be used. The overhead reduction may be particularly advantageous in beam forming MIMO (multiple input multiple output) operation with, for example four or more antennas. In situations such as the HetNet scenario outlined above, there may be reduced interference from common signals.
In LTE release 8/9/10, it has been proposed for one carrier only to allow slow turning on or turning off of the carrier to save energy according to traffic variations. Even if only one user is connected in the network, some signals are still needed to be transmitted to assist the UE in measuring the reference signal received power (RSRP), or to acquire broadcasting information. Regular per-subframe common signal transmission may waste energy.
Some further enhancements have also been proposed to keep good compatibility for the NCT design without introducing a new discovery signal. According to this proposal, the eNB dormant state is characterised by DTX ON and DTX OFF periods. No common signals/channels are transmitted during the eNB DTX OFF period. During the eNB DTX ON period, some primary synchronisation signals (PSS) and secondary synchronisation signals (SSS) and common reference signals (CRS) are transmitted for the purpose of synchronisation and RRM measurements. The eNB DTX ON state appears periodically. If the eNB DTX ON period falls within an eNB active period, then there may not be any additional transmission of the common signals besides those that would be transmitted during the eNB active state in any case.
Reference is made to
During the active state 502, the state 520 is such that common signals are transmitted. In other words the base station operates as “normal”, transmitting signals to user equipment. In the second dormant state 504, again there is a first DTX OFF state 522 followed by a DTX ON state 524 followed by a DTX OFF state 526. The DTX ON state may last for a relatively large number of subframes and may for example last for more than 10 subframes.
In the proposals of
In some embodiments a new working mode of an eNB may be provided.
Some embodiments may provide base stations which support a dual dormant/active state. This may mean DTX (discontinuous transmission) like base station behaviour, with for example relatively long DTX cycles. The UE may perform procedures to take into account the state of the base station. In some embodiments there may be a reduced CRS in the active state.
Some embodiments may allow for base station energy saving, utilising the dormancy operation. Signals may be provided to allow for dormant cell discovery and RRM (radio resource management) measurements.
Some embodiments relate to the use of the eNodeB (eNB) dormancy feature of a carrier for example in the context of small cells. By way of example a small cell may be a pico cell, a HetNet cell or the like.
However, even in the event a cell/carrier is not carrying any traffic, common signals and channels such as one or more of PDCCH (Physical Downlink Control Channel), PHICH (Physical Hybrid ARQ (Automatic Repeat-reQuest) Indicator Channel), PCFICH (Physical Control Format Indicator Channel), PSS/SSS (Primary Synchronization Signal/Secondary Synchronization Signal), PCH (Paging Channel), PBCH (Physical Broadcast Channel), SIB (system information block), CRS (Common (cell specific) Reference Signal) and CSI-RS (Channel State Information Reference Signal) may be required, for example, in order to support mobility. In other words reference signals transmitted by a base station, and received by a user equipment, may comprise any of the above types of signal.
An embodiment provides a base station which is configured to operate at at least three levels of activity: a first level of activity, a second level of activity, and a third level of activity. According to an embodiment the first level of activity is higher than the second level of activity, and the second level of activity is higher than the third level of activity. When a base station is operating at the first level of activity it may be considered to be operating in an “active” state. When the base station is operating at the second level of activity it may be considered to be in a first dormant state. When the base station is operating at the third level of activity it may be considered to be operating in a second dormant state.
Likewise an embodiment provides a user equipment which has at least three connection modes: a first connection mode, a second connection mode, and a third connection mode. These “modes” relate to its connection to a base station. In the first connection mode the user equipment may be considered “active”, and operating at a first level of activity. When in the second connection mode the user equipment operates at a second activity level which is lower than the first activity level. When in the third connection mode the user equipment operates at a third activity level that is lower than the second activity level. The connection mode of the user equipment is dependent upon the activity state of the base station.
The first active state of the base station may be considered a state of “normal” operation, in which the base station transmits common reference signals (such as the list of reference signals referred to above) to a user equipment, as well as transmitting data to and receiving data from the user equipment. This may be considered the first activity level. Here the reference signal transmission could be the same as that of existing LTE release 8/9/10.
When the base station is operating in the first dormant state it operates at the second activity level. In this mode the base station will send reference signals to the user equipment, with no further data transmission. The reference signals may be sent less often than when operating at the first activity level, for example with a longer periodicity. Alternatively the base station may transmit data similarly as on a carrier of new carrier type (NCT).
When operating in the second dormant state the base station operates at the third activity level. In the second dormant state the base station may be in a fully dormant state in which no data or reference signals are sent. Alternatively reference signals are transmitted occasionally so as to maintain cell identification to the user equipment. In the third activity level the base station transmits reference signals less frequently than when operating at the second activity level. The reference signals could comprise a common reference signal, synchronization signal or any cell identification signal.
Accordingly the first activity level may be considered a level of activity higher than the second activity level, which in turn is a higher activity level than the third activity level.
As shown the UE 610 can perform data transmission only when the eNB 600 is in one of its active states 602 or 606. During the dormant state the UE 610 is configured to still receive the common/discovery signals so as to maintain the alive state and to keep DL synchronisation with the eNB, but there is no data transmission by the UE during the dormant period 604 and 608.
The common signals/discovery signals transmitted in the dormant period by the eNB 600 may be transmitted relatively often to allow for UEs to be synchronised during the eNB dormant period. This assumes that the UE 610 is “attached” to the eNB 600 and that it needs to keep DL synchronization between consecutive transmissions of common signals/discovery signals. It will also be appreciated that these common signals/discovery signals may also be transmitted during the “active” period so as to maintain synchronisation during that time. The periodicity of the transmission of the common signals in the dormant period may be different from that of the active period. In one embodiment the signals are transmitted less often in the dormant period than they are in the active period. In another embodiment common/discovery signal requirement can be relaxed, with the common/discovery signals being periodically transmitted to recover DL synchronization.
The UE 610 maintains its connection with the eNB 600 in the carrier/cell whether the eNB 600 is active or dormant. When the cell is a primary cell (P-cell), then this connection may be a radio resource control (RRC) connection, for the purpose of a UE attached in the network. When the cell is a secondary cell (S-cell), then this cell will keep activation for this UE. As previously discussed the UE may be silent for data transmission when the eNB 600 is in the dormant period, but the UE may keep synchronisation with the eNB 600 and perform radio resource management (RRM) measurement. As a special implementation case, if the NB has data transmission in dormant state, UE still could receive the related data signals.
As shown at 712 the UE is in an active state when the eNB 700 is also in an active state. When in the active state 712 the UE may be in a RRC connected mode. When the eNB 700 switches from the active mode 702 to the dormant mode 704, the UE 710 moves from the active mode 712 to an idle mode 714. The idle mode 714 may be an RRC idle mode. As shown at 716 when the eNB 700 moves from the dormant state 704 to the active state 706, then the UE 710 can re-establish the RRC connection if new traffic is coming. In the long dormancy application of
As shown in
If the connection is a secondary cell connection (S-cell) then this state or carrier could be deactivated when the eNB is dormant.
Thus when the eNB is under a relatively low load the eNB can apply the long dormancy procedure. The UE can stay in the idle mode when the eNB is dormant.
Where there is a higher load (albeit a lower load than when in a fully active data transmission state), the eNB can apply the short dormancy regime. According to this regime the UE can maintain the RRC connection, but may transmit data packets only when in the active state. Interference coordination may also be used between different cells.
It will be appreciated that the examples of
The cell-load level or threshold at which the eNB and UE switch between their respective modes may be fixed. The threshold levels may be set by the network and then communicated to the eNB. Alternatively the levels can be set by the eNB themselves. These threshold levels can be altered over time. For example the network may communicate new threshold levels to the eNB.
In some embodiments the eNB operates in the first mode of operation when a first threshold level is satisfied, and operates in the second mode of operation when a second threshold level is satisfied that is lower than the first threshold level, and operates in the third mode of operation when a third threshold level is satisfied that is lower than the second threshold level. The threshold level may be associated with a cell-load threshold level, but could also be associated with other parameters. For example such a parameter may be neighbouring eNB requirement. That is the eNB may determine in which mode to operate in dependence on an interference level in a neighbouring cell. That information may be obtained from the neighbouring eNB. Another parameter may be paging information, or UE DL data arrival information from the network. For example an eNB may receive urgent paging calls for the UEs attached to the eNB. The eNB may then take the decision to wake up, for example switching from the second mode to the first mode, or from the third mode to the first mode. Another parameter may be UE triggering information. For example if a UE has UL data packets that need to be sent, the eNB will receive the UE triggering information and then determine its state transition e.g. from the second mode to the first mode, or from the third mode to the first mode.
The above three activity level states can be switched either by eNB determination or UE triggered. The eNB may switch activity state based on cell load or other information, while the UE may trigger eNB state change based on UE's traffic needs.
It will also be appreciated that the eNB can move between activity levels in any fashion, as shown in
The UE can move between connection modes in any fashion, as shown in
In embodiments the UE connection modes shown in
The UE may be configured to map itself to the eNB state i.e. the eNB state “leads” and the UE state “follows”. In another embodiment the eNB is configured to map itself to the UE state i.e. the UE state “leads” and the eNB state “follows”.
It will also be appreciated that the time intervals between transmission of the reference signals can be fixed, and subsequently updated, in a similar way e.g. by communication with the network.
The time interval between the transmission of subsequent reference signals may be periodic. Alternatively the time interval between subsequent reference signals may be non-constant.
It will also be appreciated that
By tailoring the dormancy cycle to the traffic load conditions then the power consumption of the eNB and one or more UEs can be reduced since they can be put into a dormant or idle mode as necessary.
It will be appreciated that the base stations or eNBs according to the embodiments may comprise the features of a control apparatus as described with respect to
Likewise UE according to embodiments of the present invention may comprise features of a UE discussed with respect to
The operations may also be at least partly carried out as a cloud service in which case the apparatus may be located in a server or host or be partly in a server or host and partly in a node. The radio parts may be a remote radio head.
Embodiments may be applied to machine-to-machine communications. User device energy saving and interference control issues are of importance especially in machine-to-machine (M2M) or machine-type communications, such as conveying metering or sensor data to a central processing unit. This data may comprise information on temperature, humidity, energy or water consumption etc. The communications may also comprise control functions, for example for preheating a vehicle or second lodging. This kind of communication is typically of such a nature that it can be delayed for a short period of time and thus dormancy functionality is well-suited for this purpose.
The required data processing apparatus and functions of a base station apparatus, a communication device and any other appropriate apparatus may be provided by means of one or more data processors. The described functions at each end may be provided by separate processors or by an integrated processor. The data processors may be of any type suitable to the local technical environment, and may include one or more of general purpose computers, special purpose computers, microprocessors, digital signal processors (DSPs), application specific integrated circuits (ASIC), gate level circuits and processors based on multi core processor architecture, as non limiting examples. The data processing may be distributed across several data processing modules. A data processor may be provided by means of, for example, at least one chip. Appropriate memory capacity can also be provided in the relevant devices. The memory or memories may be of any type suitable to the local technical environment and may be implemented using any suitable data storage technology, such as semiconductor based memory devices, magnetic memory devices and systems, optical memory devices and systems, fixed memory and removable memory.
In general, the various embodiments may be implemented in hardware or special purpose circuits, software, logic or any combination thereof. Some aspects of the invention may be implemented in hardware, while other aspects may be implemented in firmware or software which may be executed by a controller, microprocessor or other computing device, although the invention is not limited thereto. While various aspects of the invention may be illustrated and described as block diagrams, flow charts, or using some other pictorial representation, it is well understood that these blocks, apparatus, systems, techniques or methods described herein may be implemented in, as non-limiting examples, hardware, software, firmware, special purpose circuits or logic, general purpose hardware or controller or other computing devices, or some combination thereof. The software may be stored on such physical media as memory chips, or memory blocks implemented within the processor, magnetic media such as hard disk or floppy disks, and optical media such as for example DVD and the data variants thereof, CD.
The foregoing description has provided by way of exemplary and non-limiting examples a full and informative description of the exemplary embodiment of this invention. However, various modifications and adaptations may become apparent to those skilled in the relevant arts in view of the foregoing description, when read in conjunction with the accompanying drawings and the appended claims. However, all such and similar modifications of the teachings of this invention will still fall within the scope of this invention as defined in the appended claims. Indeed there is a further embodiment comprising a combination of one or more of any of the other embodiments previously discussed.
Lunttila, Timo Erkki, Rosa, Claudio, Miao, De Shan
Patent | Priority | Assignee | Title |
11509408, | Jul 30 2021 | INNTOT TECHNOLOGIES PRIVATE LIMITED | System and method for large data transmission in digital radio broadcasting |
Patent | Priority | Assignee | Title |
5896561, | Apr 06 1992 | AVAGO TECHNOLOGIES INTERNATIONAL SALES PTE LIMITED | Communication network having a dormant polling protocol |
20020001299, | |||
20080039032, | |||
20080181127, | |||
20110128865, | |||
20110244792, | |||
20130258919, | |||
20140341140, | |||
CN102210190, |
Executed on | Assignor | Assignee | Conveyance | Frame | Reel | Doc |
Mar 14 2013 | HMD Global Oy | (assignment on the face of the patent) | / | |||
Sep 07 2015 | LUNTTILA, TIMO ERKKI | NOKIA SOLUTIONS AND NETWORKS OY | ASSIGNMENT OF ASSIGNORS INTEREST SEE DOCUMENT FOR DETAILS | 036556 | /0714 | |
Sep 07 2015 | ROSA, CLAUDIO | NOKIA SOLUTIONS AND NETWORKS OY | ASSIGNMENT OF ASSIGNORS INTEREST SEE DOCUMENT FOR DETAILS | 036556 | /0714 | |
Sep 09 2015 | MIAO, DE SHAN | NOKIA SOLUTIONS AND NETWORKS OY | ASSIGNMENT OF ASSIGNORS INTEREST SEE DOCUMENT FOR DETAILS | 036556 | /0714 | |
Nov 17 2017 | NOKIA SOLUTIONS AND NETWORKS OY | HMD Global Oy | ASSIGNMENT OF ASSIGNORS INTEREST SEE DOCUMENT FOR DETAILS | 045085 | /0800 |
Date | Maintenance Fee Events |
Date | Maintenance Schedule |
Jun 15 2024 | 4 years fee payment window open |
Dec 15 2024 | 6 months grace period start (w surcharge) |
Jun 15 2025 | patent expiry (for year 4) |
Jun 15 2027 | 2 years to revive unintentionally abandoned end. (for year 4) |
Jun 15 2028 | 8 years fee payment window open |
Dec 15 2028 | 6 months grace period start (w surcharge) |
Jun 15 2029 | patent expiry (for year 8) |
Jun 15 2031 | 2 years to revive unintentionally abandoned end. (for year 8) |
Jun 15 2032 | 12 years fee payment window open |
Dec 15 2032 | 6 months grace period start (w surcharge) |
Jun 15 2033 | patent expiry (for year 12) |
Jun 15 2035 | 2 years to revive unintentionally abandoned end. (for year 12) |